Android Open Source - Fast Database Helper

From Project

Back to project page Fast.
License

The source code is released under:
GNU General Public License
If you think the Android project Fast listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.
Java Source Code

package com.example.fast;
//from  w ww .  j  av  a 2  s  . c  om
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.content.Context;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;

/**
 * Our extension of the SQLite Helper.  Based off of ToDo List lab and the Google Developer website.
 *
 */
public class DatabaseHelper extends SQLiteOpenHelper{
     
      private static String DB_NAME = "faster2.db";
      private static final String DB_CREATE = "CREATE TABLE fast_table(_id INTEGER PRIMARY KEY autoincrement, username TEXT not null,"
          + " average_speed NUMERIC not null, max_speed NUMERIC not null, distance NUMERIC not null, " 
          + " average_heartrate NUMERIC not null);";
      private SQLiteDatabase myDatabase; 
      private final Context myContext;
        private static final int DATABASE_VERSION = 14;

        public DatabaseHelper(Context context) {
            super(context, DB_NAME, null, DATABASE_VERSION);
            this.myContext = context;
        }

   
        /**
       * Creates an empty database on the system and rewrites it with your own database.
       * */
      public void createDatabase() throws IOException{
   
        boolean dbExist = checkDatabase();
   
        if(dbExist){
        }else{
            this.getReadableDatabase();
   
            try {
            copyDatabase();
          } catch (IOException e) {
              throw new Error("Error copying database");
            }
        }
   
      }
   
      /**
       * Check if the database already exist to avoid re-copying the file each time you open the application.
       * @return true if it exists, false if it doesn't
       */
      private boolean checkDatabase(){
   
        SQLiteDatabase checkDB = null;
   
        try{
          String myPath = DB_NAME;
          checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.NO_LOCALIZED_COLLATORS | SQLiteDatabase.OPEN_READWRITE);
   
        }catch(SQLiteException e){
        }
   
        if(checkDB != null){
          checkDB.close();
        }
   
        return checkDB != null ? true : false;
      }
   
      /**
       * Copies your database from your local assets-folder to the just created empty database in the
       * system folder, from where it can be accessed and handled.
       * This is done by transfering bytestream.
       * */
      private void copyDatabase() throws IOException{
   
        //Open your local db as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);
   
        // Path to the just created empty db
        String outFileName = DB_NAME;
   
        //Open the empty db as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);
   
        //transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer))>0){
          myOutput.write(buffer, 0, length);
        }
   
        //Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();
   
      }
   
      public void openDatabase() throws SQLException{
   
        //Open the database
          String myPath = DB_NAME;
        myDatabase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.NO_LOCALIZED_COLLATORS | SQLiteDatabase.OPEN_READWRITE);
   
      }
   
      @Override
    public synchronized void close() {
   
            if(myDatabase != null)
              myDatabase.close();
   
            super.close();
   
    }
   
    @Override
    public void onCreate(SQLiteDatabase db) {
      //db.execSQL("DROP TABLE IF EXISTS fast_table");
      db.execSQL(DB_CREATE);
    }
   
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
   
      db.execSQL("DROP TABLE IF EXISTS fast_table");
            onCreate(db);
    }
}
Java Source Code List
